| A | B |
|---|
| ecosystem | a collection of all the organisms that live in a particular place, together with their nonliving, or physical, environment. |
| ecology | Scientific study of interactions among organisms and between organisms and their environment |
| bioshere | Contains the combined portions of the planet in which all of life exists |
| bioshere includes | land, water, and air (atmosphere) |
| Interactions within the biosphere produce | a web of interdependence (depending on each other) between organisms and the environment in which they live |
| dynamic biosphere | The interdependence of life on Earth contributes to an ever-changing biosphere |
| species | Group of organisms so similar to one another that they can breed and produce fertile offspring |
| populations | Groups of individuals that belong to the same species and live in the same area |
| communities | Assemblages (groups) of different populations that live together in a defined area |
| ecosystem | Collection of all the organisms that live in a particular place, together with their nonliving (physical) environment |
| biome | Group of ecosystems that have the same climate and dominant communities |
| Modern ecological research uses three basic approaches which rely on the application of scientific methods | observing, experimenting, modeling |
| producers | organisms that can make their own food |
| consumers | organisms that rely on other organisms for food |
| Sunlight | the main energy source for life on Earth. |
| autotrophes | make their own food = producers |
| autotrophes = producers | use energy from the environment to fuel the assembly (making) of simple inorganic compounds into complex organic molecules |
| Organic compounds | combine and recombine to form living tissue. |
| Plants, algae and cyanobacteria are autotrophes that | Capture energy from sunlight and use photosynthesis to produce food |
| Photosynthesis | plants use sunlight to convert (change) carbon dioxide and water into oxygen and energy-rich carbohydrates (sugars and starches) |
| Chemosynthesis | certain bacteria rely on energy within the chemical bonds of inorganic molecules to produce carbohydrates |
| 2 sources of energy used by autotrophes to make their own food | 1. green plants use sunlight in photosynthesis; 2. certain bacteria use chemical bonds to produce carbohydrates |
| Heterotrophes = consumers | Rely on other organisms for their energy and food supply |
| Herbivores | Type of Heterotrophe who eats plants only; ex. cows, horses, caterpillars |
| Carnivores | Type of Heterotrophe who eats meat only; ex. snakes, dogs, owls |
| Omnivores | Type of Heterotrophe who eat both plants and animals; ex. bears, crows, humans |
| Detritivores | Type of Heterotrophe who Feed on plant and animal remains and other dead matter (detritus); ex. snails, crabs, mites, earthworms |
| Decomposers | Type of Heterotrophe who break down organic matter; ex. bacteria, fungus |
| Energy flows through an ecosystem in one direction | from the sun or inorganic compounds to autotrophs (producers) and then to various heterotrophs (consumers) |
| Food Chain | Series of steps in which organisms transfer energy by eating and being eaten; ex. Grass - antelope - lion |
| Food Web | Used to describe the network of complex interactions and feeding relationships among the various organisms in an ecosystem |
| Trophic Level | Each step in a food chain or food web |
| First Trophic Level | Made up of Producers |
| Second, Third, Fourth Tropic Levels | Made up of Consumers; Each consumer depends on the trophic level below it for energy |
| Energy Pyramid | Only 10% of the energy stored in one trophic level is passed on to the next level; Organisms use much of the energy that they consume for life processes (respiration, movement, etc.); Remaining energy is released into the environment as heat |
| Biomass Pyramid | Total amount of living tissue within a given trophic level; expressed in terms of grams of organic matter per unit area; Represents the amount of potential food available for each trophic level in an ecosystem |
| Cycles of Matter | Matter is recycled within and between ecosystems |
| Biogeochemical Cycles | Pass elements, chemical compounds, and other forms of matter from one organism to another and from one part of the biosphere to anothe |
| Examples of Biogeochemical Cycles | Water Cycle; Nutrient Cycles (Carbon, Nitrogen, Phosphorus) |
| Water Cycle | Water goes into atmosphere through evaporation or plant transpiration; it condenses, then falls to earth as persipitation, then seeps into the ground for plant roots to use |
| Carbon Cycle | Carbon dioxide goes into atmosphere from respiration, decomposition, human waste, vocanic eruption, etc.; then it is used by plants in photosynthesis to produce food for consumers who then produce carbon dioxide through respiration (breathing) and waste, and decomposition when they die |
